<?php

/*

 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT

 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR

 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT

 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT

 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,

 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY

 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 *

 * This software consists of voluntary contributions made by many individuals

 * and is licensed under the LGPL. For more information, see

 * <http://www.doctrine-project.org>.

 */

namespace Doctrine\DBAL\Schema;

use \Doctrine\DBAL\Platforms\AbstractPlatform;

/**

 * Schema Diff

 *

 * @license http://www.opensource.org/licenses/lgpl-license.php LGPL

 * @link    www.doctrine-project.org

 * @copyright Copyright (C) 2005-2009 eZ Systems AS. All rights reserved.

 * @license http://ez.no/licenses/new_bsd New BSD License

 * @since   2.0

 * @version $Revision$

 * @author  Benjamin Eberlei <kontakt@beberlei.de>

 */

class SchemaDiff

{

    /**

     * All added tables

     *

     * @var array(string=>ezcDbSchemaTable)

     */

    public $newTables = array();

    /**

     * All changed tables

     *

     * @var array(string=>ezcDbSchemaTableDiff)

     */

    public $changedTables = array();

    /**

     * All removed tables

     *

     * @var array(string=>Table)

     */

    public $removedTables = array();

    /**

     * @var array

     */

    public $newSequences = array();

    /**

     * @var array

     */

    public $changedSequences = array();

    /**

     * @var array

     */

    public $removedSequences = array();

    /**

     * @var array

     */

    public $orphanedForeignKeys = array();

    /**

     * Constructs an SchemaDiff object.

     *

     * @param array(string=>Table)      $newTables

     * @param array(string=>TableDiff)  $changedTables

     * @param array(string=>bool)       $removedTables

     */

    public function __construct($newTables = array(), $changedTables = array(), $removedTables = array())

    {

        $this->newTables = $newTables;

        $this->changedTables = $changedTables;

        $this->removedTables = $removedTables;

    }

    /**

     * The to save sql mode ensures that the following things don't happen:

     *

     * 1. Tables are deleted

     * 2. Sequences are deleted

     * 3. Foreign Keys which reference tables that would otherwise be deleted.

     *

     * This way it is ensured that assets are deleted which might not be relevant to the metadata schema at all.

     *

     * @param AbstractPlatform $platform

     * @return array

     */

    public function toSaveSql(AbstractPlatform $platform)

    {

        return $this->_toSql($platform, true);

    }

    /**

     * @param AbstractPlatform $platform

     * @return array

     */

    public function toSql(AbstractPlatform $platform)

    {

        return $this->_toSql($platform, false);

    }

    /**

     * @param AbstractPlatform $platform

     * @param bool $saveMode

     * @return array

     */

    protected function _toSql(AbstractPlatform $platform, $saveMode = false)

    {

        $sql = array();

        if ($platform->supportsForeignKeyConstraints() && $saveMode == false) {

            foreach ($this->orphanedForeignKeys AS $orphanedForeignKey) {

                $sql[] = $platform->getDropForeignKeySQL($orphanedForeignKey, $orphanedForeignKey->getLocalTableName());

            }

        }

        if ($platform->supportsSequences() == true) {

            foreach ($this->changedSequences AS $sequence) {

                $sql[] = $platform->getAlterSequenceSQL($sequence);

            }

            if ($saveMode === false) {

                foreach ($this->removedSequences AS $sequence) {

                    $sql[] = $platform->getDropSequenceSQL($sequence);

                }

            }

            foreach ($this->newSequences AS $sequence) {

                $sql[] = $platform->getCreateSequenceSQL($sequence);

            }

        }

        $foreignKeySql = array();

        foreach ($this->newTables AS $table) {

            $sql = array_merge(

                $sql,

                $platform->getCreateTableSQL($table, AbstractPlatform::CREATE_INDEXES)

            );

            if ($platform->supportsForeignKeyConstraints()) {

                foreach ($table->getForeignKeys() AS $foreignKey) {

                    $foreignKeySql[] = $platform->getCreateForeignKeySQL($foreignKey, $table);

                }

            }

        }

        $sql = array_merge($sql, $foreignKeySql);

        if ($saveMode === false) {

            foreach ($this->removedTables AS $table) {

                $sql[] = $platform->getDropTableSQL($table);

            }

        }

        foreach ($this->changedTables AS $tableDiff) {

            $sql = array_merge($sql, $platform->getAlterTableSQL($tableDiff));

        }

        return $sql;

    }

}